Here are the most common Japanese menu items you will encounter and their English counterparts:
Even without a full manual, these solutions address frequent complaints:
Many users simply disable the navigation portion and use the unit as an amplifier for an external Bluetooth FM transmitter or AUX input (if available). The screen then serves as a clock and basic radio.
from Panasonic Japan's support site. You can upload this PDF to tools like Google Translate to convert specific pages into English. Changing language for on-screen display
Car Navigation System Operation Manual (English) For imported / Japanese-market units
: Explains general button functions and navigation basics. How to Navigate in English
If you need additional help or have questions about your Panasonic CN-HDS625D, here are some additional resources: